In the prior art, communication between network devices are typically achieved by multiple routers and/or switches through forwarding packets. Generally, each router or switch is provided with a control plane, a management plane and a data plane. A user manages the router or the switch via the management plane, the control plane operates various forwarding protocols, computes paths, generates forwarding entries, and issues the forwarding entries to the data plane, and the data plane forwards the packet according to the forwarding entries.
Since each router or switch in the network performs operations of the above three planes, when a network protocol is updated, each router or switch needs to be configured and maintained, then manageability of a complex network is poor.